慢查询日志分析（mysql）
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2022-05-07 19:53:09
开启慢查询日志之后，慢查询sql会被存到数据库系统表mysql.slow_log或是文件中，可参考。有两个工具可以帮助我们分析输出报告，分别是mysqldumpslow和pt-query-digest. mysqldumpslow mysqldumpslow是mysql自身提供的日志分析工具，一般在 ......
开启慢查询日志之后，慢查询sql会被存到数据库系统表mysql.slow_log或是文件中，可参考。有两个工具可以帮助我们分析输出报告，分别是mysqldumpslow和pt-query-digest.
mysqldumpslow
mysqldumpslow是mysql自身提供的日志分析工具，一般在mysql的bin目录下
帮助信息
1 $ mysqldumpslow.pl --help 2 Usage: mysqldumpslow [ OPTS... ] [ LOGS... ] 3 4 Parse and summarize the MySQL slow query log. Options are 5 6 --verbose verbose 7 --debug debug 8 --help write this text to standard output 9 10 -v verbose 11 -d debug 12 -s ORDER what to sort by (al, at, ar, c, l, r, t), 'at' is default 13 al: average lock time 14 ar: average rows sent 15 at: average query time 16 c: count 17 l: lock time 18 r: rows sent 19 t: query time 20 -r reverse the sort order (largest last instead of first) 21 -t NUM just show the top n queries 22 -a don't abstract all numbers to N and strings to 'S' 23 -n NUM abstract numbers with at least n digits within names 24 -g PATTERN grep: only consider stmts that include this string 25 -h HOSTNAME hostname of db server for *-slow.log filename (can be wildcard), 26 default is '*', i.e. match all 27 -i NAME name of server instance (if using mysql.server startup script) 28 -l don't subtract lock time from total time
1 -s, 是表示按照何种方式排序 2 c: 访问计数 3 4 l: 锁定时间 5 6 r: 返回记录 7 8 t: 查询时间 9 10 al:平均锁定时间 11 12 ar:平均返回记录数 13 14 at:平均查询时间 15 16 -t, 是top n的意思，即为返回前面多少条的数据； 17 -g, 后边可以写一个正则匹配模式，大小写不敏感的； 18 19 比如: 20 得到返回记录集最多的10个SQL。 21 mysqldumpslow -s r -t 10 /database/mysql/mysql06_slow.log 22 23 得到访问次数最多的10个SQL 24 mysqldumpslow -s c -t 10 /database/mysql/mysql06_slow.log 25 26 得到按照时间排序的前10条里面含有左连接的查询语句。 27 mysqldumpslow -s t -t 10 -g “left join” /database/mysql/mysql06_slow.log 28 29 另外建议在使用这些命令时结合 | 和more 使用 ，否则有可能出现刷屏的情况。 30 mysqldumpslow -s r -t 20 /mysqldata/mysql/mysql06-slow.log | more
如果不能执行，可以先安装perl，然后通过perl mysqldumpslow xxx.log
pt-query-digest 参考
个人觉的pt-query-digest分析报告比mysqldumpslow好用。pt-query-digest可以不仅可以分析slowlog，还可以分析binlog，generallog等。
下载安装 https://www.percona.com/downloads/percona-toolkit/LATEST/
在windows下，下载tar.gz包，解压之后，使用perl命令运行
帮助信息
$ perl pt-query-digest --help
pt-query-digest analyzes MySQL queries from slow, general, and binary log files.
It can also analyze queries from C<SHOW PROCESSLIST> and MySQL protocol data
from tcpdump. By default, queries are grouped by fingerprint and reported in
descending order of query time (i.e. the slowest queries first). If no C<FILES>
are given, the tool reads C<STDIN>. The optional C<DSN> is used for certain
options like L<"--since"> and L<"--until">. For more details, please use the
--help option, or try 'perldoc pt-query-digest' for complete documentation.
Usage: pt-query-digest [OPTIONS] [FILES] [DSN]
Options:
--ask-pass Prompt for a password when connecting to MySQL
--attribute-aliases=a List of attribute|alias,etc (default db|Schema)
--attribute-value-limit=i A sanity limit for attribute values (default 0)
--charset=s -A Default character set
--config=A Read this comma-separated list of config files;
if specified, this must be the first option on
the command line
--[no]continue-on-error Continue parsing even if there is an error (
default yes)
--[no]create-history-table Create the --history table if it does not exist (
default yes)
--[no]create-review-table Create the --review table if it does not exist (
default yes)
--daemonize Fork to the background and detach from the shell
--database=s -D Connect to this database
--defaults-file=s -F Only read mysql options from the given file
--embedded-attributes=a Two Perl regex patterns to capture pseudo-
attributes embedded in queries
--expected-range=a Explain items when there are more or fewer than
expected (default 5,10)
--explain=d Run EXPLAIN for the sample query with this DSN
and print results
--filter=s Discard events for which this Perl code doesn't
return true
--group-by=A Which attribute of the events to group by (
default fingerprint)
--help Show help and exit
--history=d Save metrics for each query class in the given
table. pt-query-digest saves query metrics (
query time, lock time, etc.) to this table so
you can see how query classes change over time
--host=s -h Connect to host
--ignore-attributes=a Do not aggregate these attributes (default arg,
cmd, insert_id, ip, port, Thread_id, timestamp,
exptime, flags, key, res, val, server_id,
offset, end_log_pos, Xid)
--inherit-attributes=a If missing, inherit these attributes from the
last event that had them (default db,ts)
--interval=f How frequently to poll the processlist, in
seconds (default .1)
--iterations=i How many times to iterate through the collect-
and-report cycle (default 1)
--limit=A Limit output to the given percentage or count (
default 95%:20)
--log=s Print all output to this file when daemonized
--order-by=A Sort events by this attribute and aggregate
function (default Query_time:sum)
--outliers=a Report outliers by attribute:percentile:count (
default Query_time:1:10)
--output=s How to format and print the query analysis
results (default report)
--password=s -p Password to use when connecting
--pid=s Create the given PID file
--port=i -P Port number to use for connection
--preserve-embedded-numbers Preserve numbers in database/table names when
fingerprinting queries
--processlist=d Poll this DSN's processlist for queries, with --
interval sleep between
--progress=a Print progress reports to STDERR (default time,
30)
--read-timeout=m Wait this long for an event from the input; 0 to
wait forever (default 0). Optional suffix s=
seconds, m=minutes, h=hours, d=days; if no
suffix, s is used.
--[no]report Print query analysis reports for each --group-by
attribute (default yes)
--report-all Report all queries, even ones that have been
reviewed
--report-format=A Print these sections of the query analysis
report (default rusage,date,hostname,files,
header,profile,query_report,prepared)
--report-histogram=s Chart the distribution of this attribute's
values (default Query_time)
--resume=s If specified, the tool writes the last file
offset, if there is one, to the given filename
--review=d Save query classes for later review, and don't
report already reviewed classes
--run-time=m How long to run for each --iterations. Optional
suffix s=seconds, m=minutes, h=hours, d=days; if
no suffix, s is used.
--run-time-mode=s Set what the value of --run-time operates on (
default clock)
--sample=i Filter out all but the first N occurrences of
each query
--set-vars=A Set the MySQL variables in this comma-separated
list of variable=value pairs
--show-all=H Show all values for these attributes
--since=s Parse only queries newer than this value (parse
queries since this date)
--slave-password=s Sets the password to be used to connect to the
slaves
--slave-user=s Sets the user to be used to connect to the slaves
--socket=s -S Socket file to use for connection
--timeline Show a timeline of events
--type=A The type of input to parse (default slowlog)
--until=s Parse only queries older than this value (parse
queries until this date)
--user=s -u User for login if not current user
--variations=A Report the number of variations in these
attributes' values
--version Show version and exit
--[no]version-check Check for the latest version of Percona Toolkit,
MySQL, and other programs (default yes)
--[no]vertical-format Output a trailing "\G" in the reported SQL
queries (default yes)
--watch-server=s This option tells pt-query-digest which server
IP address and port (like "10.0.0.1:3306") to
watch when parsing tcpdump (for --type tcpdump);
all other servers are ignored
Option types: s=string, i=integer, f=float, h/H/a/A=comma-separated list, d=DSN, z=size, m=time
Rules:
This tool accepts additional command-line arguments. Refer to the SYNOPSIS and usage information for details.
DSN syntax is key=value[,key=value...] Allowable DSN keys:
KEY COPY MEANING
=== ==== =============================================
A yes Default character set
D yes Default database to use when connecting to MySQL
F yes Only read default options from the given file
P yes Port number to use for connection
S yes Socket file to use for connection
h yes Connect to host
p yes Password to use when connecting
t no The --review or --history table
u yes User for login if not current user
If the DSN is a bareword, the word is treated as the 'h' key.
Options and values after processing arguments:
--ask-pass FALSE
--attribute-aliases db|Schema
--attribute-value-limit 0
--charset (No value)
--config /etc/percona-toolkit/percona-toolkit.conf,/etc/percona-toolkit/pt-query-digest.conf,/c/Users/Admin/.percona-toolkit.conf,/c/Users/Admin/.pt-query-digest.conf
--continue-on-error TRUE
--create-history-table TRUE
--create-review-table TRUE
--daemonize FALSE
--database (No value)
--defaults-file (No value)
--embedded-attributes (No value)
--expected-range 5,10
--explain (No value)
--filter (No value)
--group-by fingerprint
--help TRUE
--history (No value)
--host (No value)
--ignore-attributes arg,cmd,insert_id,ip,port,Thread_id,timestamp,exptime,flags,key,res,val,server_id,offset,end_log_pos,Xid
--inherit-attributes db,ts
--interval .1
--iterations 1
--limit 95%:20
--log (No value)
--order-by Query_time:sum
--outliers Query_time:1:10
--output report
--password (No value)
--pid (No value)
--port (No value)
--preserve-embedded-numbers FALSE
--processlist (No value)
--progress time,30
--read-timeout 0
--report TRUE
--report-all FALSE
--report-format rusage,date,hostname,files,header,profile,query_report,prepared
--report-histogram Query_time
--resume (No value)
--review (No value)
--run-time (No value)
--run-time-mode clock
--sample (No value)
--set-vars
--show-all
--since (No value)
--slave-password (No value)
--slave-user (No value)
--socket (No value)
--timeline FALSE
--type slowlog
--until (No value)
--user (No value)
--variations
--version FALSE
--version-check TRUE
--vertical-format TRUE
--watch-server (No value)
pt-query-digest [OPTIONS] [FILES] [DSN] --create-review-table 当使用--review参数把分析结果输出到表中时，如果没有表就自动创建。 --create-history-table 当使用--history参数把分析结果输出到表中时，如果没有表就自动创建。 --filter 对输入的慢查询按指定的字符串进行匹配过滤后再进行分析 --limit 限制输出结果百分比或数量，默认值是20,即将最慢的20条语句输出，如果是50%则按总响应时间占比从大到小排序，输出到总和达到50%位置截止。 --host mysql服务器地址 --user mysql用户名 --password mysql用户密码 --history 将分析结果保存到表中，分析结果比较详细，下次再使用--history时，如果存在相同的语句，且查询所在的时间区间和历史表中的不同，则会记录到数据表中，可以通过查询同一CHECKSUM来比较某类型查询的历史变化。 --review 将分析结果保存到表中，这个分析只是对查询条件进行参数化，一个类型的查询一条记录，比较简单。当下次使用--review时，如果存在相同的语句分析，就不会记录到数据表中。 --output 分析结果输出类型，值可以是report(标准分析报告)、slowlog(Mysql slow log)、json、json-anon，一般使用report，以便于阅读。 --since 从什么时间开始分析，值为字符串，可以是指定的某个”yyyy-mm-dd [hh:mm:ss]”格式的时间点，也可以是简单的一个时间值：s(秒)、h(小时)、m(分钟)、d(天)，如12h就表示从12小时前开始统计。 --until 截止时间，配合—since可以分析一段时间内的慢查询。
输出结果分析
分为三部分
第一部分 总体统计结果
overall：总共统计结果
time range：查询执行的时间范围
unique：唯一查询数量，即对查询条件进行参数化以后，总共有多少个不同的查询
total：总计
min：最小
max：最大
avg：平均
95%：把所有值从小到大排列，位置位于95%的那个数，这个数一般最具参考价值
median：中位数，把所有值从小到大排列，位置位于中间那个数
# 该工具执行日志分析的用户时间，系统时间，物理内存占用大小，虚拟内存占用大小 # 343ms user time, 78ms system time, 0 rss, 0 vsz # 工具执行时间 # Current date: Thu Mar 29 15:51:38 2018 # 运行分析工具的主机名 # Hostname: NB2015041602 # 被分析的文件名 # Files: /d/xampp/mysql/data/NB2015041602-slow.log # 语句总数量，唯一的语句数量，QPS，并发数 # Overall: 5 total, 3 unique, 0.00 QPS, 0.05x concurrency ________________ # 日志记录的时间范围 # Time range: 2018-03-28 14:02:06 to 14:22:10 # 属性 总计 最小 最大 平均 95% 标准 中等 # Attribute total min max avg 95% stddev median # ============ ======= ======= ======= ======= ======= ======= ======= # 语句执行时间 # Exec time 60s 10s 17s 12s 17s 3s 11s # 锁占用时间 # Lock time 1ms 0 500us 200us 490us 240us 0 # 发送到客户端的行数 # Rows sent 50 10 10 10 10 0 10 # select语句扫描行数 # Rows examine 629.99k 45.43k 146.14k 126.00k 143.37k 39.57k 143.37k # 查询的字符数 # Query size 2.81k 235 1.36k 575.40 1.33k 445.36 234.30
第二部分 查询分组统计结果
rank：所有语句的排序，默认按照查询时间降序排序，通过--order-by指定
query id：语句的id，（去掉多余空格和文本字符，计算hash值）
response：总的响应时间
time：该查询在本次分析中总的时间占比
calls：执行次数，即本次分析总共有多少条这种类型的查询语句
r/call：平均每次执行的响应时间
v/m：响应时间variance-to-mean的比率
item：查询对象
# Profile # Rank Query ID Response time Calls R/Call V/M Item # ==== ================== ============= ===== ======= ===== ============== # 1 0x96112A601F7BCCC0 32.9042 55.0% 3 10.9681 0.01 SELECT affiliatemerchant_list user_list # 2 0x70885F9703A0E38D 17.2162 28.8% 1 17.2162 0.00 SELECT normalmerchant merchant_mapping normalmerchant_addinfo merchant_search_filter affiliatemerchant_list user_list # 3 0x43D8527285567FC4 9.7367 16.3% 1 9.7367 0.00 SELECT affiliatemerchant_list user_list affiliatemerchant_list user_list
第三部分 每一种查询的详细统计结果
id：查询的id号，和上面的query id对应
databases：数据库名
users：各个用户执行的次数（占比）
query_time_distribution：查询时间分布，长短体现区间占比
tables：查询中设计到的表
explain：sql语句
# Query 1: 0.00 QPS, 0.03x concurrency, ID 0x96112A601F7BCCC0 at byte 2647
# This item is included in the report because it matches --limit.
# Scores: V/M = 0.01
# Time range: 2018-03-28 14:03:31 to 14:19:54
# Attribute pct total min max avg 95% stddev median
# ============ === ======= ======= ======= ======= ======= ======= =======
# Count 60 3
# Exec time 54 33s 11s 11s 11s 11s 243ms 11s
# Lock time 50 500us 0 500us 166us 490us 231us 0
# Rows sent 60 30 10 10 10 10 0 10
# Rows examine 69 438.42k 146.14k 146.14k 146.14k 146.14k 0 146.14k
# Query size 24 707 235 236 235.67 234.30 0 234.30
# String:
# Databases database_base
# Hosts localhost
# Users root
# Query_time distribution
# 1us
# 10us
# 100us
# 1ms
# 10ms
# 100ms
# 1s
# 10s+ ################################################################
# Tables
# SHOW TABLE STATUS FROM `database_base` LIKE 'table_list1'\G
# SHOW CREATE TABLE `database_base`.`table_list1`\G
# SHOW TABLE STATUS FROM `database_base` LIKE 'user_list'\G
# SHOW CREATE TABLE `database_base`.`user_list`\G
# EXPLAIN /*!50100 PARTITIONS*/
select SQL_CALC_FOUND_ROWS al.*, ul.Alias as userName
FROM table_list1 al
LEFT JOIN user_list ul ON ul.ID = al.UserId
WHERE TRUE AND (al.SupportCountrys LIKE '%%')
limit 80, 10\G
pt-query-digest用法示例（未测试）
直接分析慢查询文件
pt-query-digest slow.log > slow_report.log
分析最近12小时内的查询
pt-query-digest --since=12h slow.log > slow_report2.log
分析指定时间范围内的查询
pt-query-digest slow.log --since '2017-01-07 09:30:00' --until '2017-01-07 10:00:00'> > slow_report3.log
分析含有select语句的慢查询
pt-query-digest --filter '$event->{fingerprint} =~ m/^select/i' slow.log> slow_report4.log
针对某个用户的慢查询
pt-query-digest --filter '($event->{user} || "") =~ m/^root/i' slow.log> slow_report5.log
查询所有全表扫描或full join的慢查询
pt-query-digest --filter '(($event->{Full_scan} || "") eq "yes") ||(($event->{Full_join} || "") eq "yes")' slow.log> slow_report6.log
把查询保存到query_review表
pt-query-digest --user=root –password=abc123 --review h=localhost,D=test,t=query_review--create-review-table slow.log
把查询保存到query_history表
pt-query-digest --user=root –password=abc123 --review h=localhost,D=test,t=query_history--create-review-table slow.log_0001
pt-query-digest --user=root –password=abc123 --review h=localhost,D=test,t=query_history--create-review-table slow.log_0002
通过tcpdump抓取的tcp协议数据，然后分析
tcpdump -s 65535 -x -nn -q -tttt -i any -c 1000 port 3306 > mysql.tcp.txt
pt-query-digest --type tcpdump mysql.tcp.txt> slow_report9.log
分析biglog
mysqlbinlog mysql-bin.000093 > mysql-bin000093.sql
pt-query-digest --type=binlog mysql-bin000093.sql > slow_report10.log
分析general log
pt-query-digest --type=genlog localhost.log > slow_report11.log